title: Pathologic response to preoperative chemotherapy: a new outcome end point after resection of hepatic colorectal metastases.
abstract: OBJECTIVE
  The primary goal of this study was to evaluate whether pathologic response to chemotherapy predicts patient survival after preoperative chemotherapy and resection of colorectal liver metastases (CLM). The secondary goal of the study was to identify the clinical predictors of pathologic response.
  
  
  METHODS
  A retrospective review was performed of 305 patients who underwent preoperative irinotecan- or oxaliplatin-based chemotherapy, followed by resection of CLM. Pathologic response was systematically evaluated and reported as the mean of the percentage of cancer cells remaining within each tumor. Univariate and multivariate analyses were performed to identify the predictors of pathologic response and survival.
  
  
  RESULTS
  Cumulative 5-year overall survival rates by pathologic response status were as follows: 75% complete response (no residual cancer cells), 56% major response (1% to 49% residual cancer cells), and 33% minor response (> or = 50% residual cancer cells; complete v major response, P = .037; major v minor response, P = .028). Multivariate analysis revealed that only surgical margin status (P = .050; hazard ratio [HR], 1.77) and pathologic response (major response: P = .034; HR, 4.80; minor response: P = .007; HR, 6.93) were independent predictors of survival. Multivariate analysis of the predictors of pathologic response revealed that carcinoembryonic antigen level < or = 5 ng/mL, tumor size < or = 3 cm, and chemotherapy with fluoropyrimidine plus oxaliplatin and bevacizumab were independent predictors of pathologic response.
  
  
  CONCLUSIONS
  Pathologic response predicts survival after preoperative chemotherapy and resection of CLM. Degree of pathologic response represents a new outcome end point for prognosis after resection of CLM.
authors.affiliation: Department of Surgical Oncology, Gastrointestinal Medical Oncology, and Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030-4009, USA.
authors.forename: Dan G
authors.initials: DG
authors.lastname: Blazer
authors.forename: Yoji
authors.initials: Y
authors.lastname: Kishi
authors.forename: Dipen M
authors.initials: DM
authors.lastname: Maru
authors.forename: Scott
authors.initials: S
authors.lastname: Kopetz
authors.forename: Yun Shin
authors.initials: YS
authors.lastname: Chun
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Overman
authors.forename: David
authors.initials: D
authors.lastname: Fogelman
authors.forename: Cathy
authors.initials: C
authors.lastname: Eng
authors.forename: David Z
authors.initials: DZ
authors.lastname: Chang
authors.forename: Huamin
authors.initials: H
authors.lastname: Wang
authors.forename: Daria
authors.initials: D
authors.lastname: Zorzi
authors.forename: Dario
authors.initials: D
authors.lastname: Ribero
authors.forename: Lee M
authors.initials: LM
authors.lastname: Ellis
authors.forename: Katrina Y
authors.initials: KY
authors.lastname: Glover
authors.forename: Robert A
authors.initials: RA
authors.lastname: Wolff
authors.forename: Steven A
authors.initials: SA
authors.lastname: Curley
authors.forename: Eddie K
authors.initials: EK
authors.lastname: Abdalla
authors.forename: Jean-Nicolas
authors.initials: JN
authors.lastname: Vauthey
mesh_terms: D000230:Adenocarcinoma / Q000556:secondary* / Q000601:surgery*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000911:Antibodies, Monoclonal / Q000008:administration & dosage; D061067:Antibodies, Monoclonal, Humanized; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D000068258:Bevacizumab; D002166:Camptothecin / Q000008:administration & dosage / Q000031:analogs & derivatives; D017024:Chemotherapy, Adjuvant; D015179:Colorectal Neoplasms / Q000401:mortality / Q000473:pathology*; D005260:Female; D006498:Hepatectomy; D006801:Humans; D000077146:Irinotecan; D008113:Liver Neoplasms / Q000188:drug therapy / Q000556:secondary* / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D009944:Organoplatinum Compounds / Q000008:administration & dosage; D000077150:Oxaliplatin; D015996:Survival Rate
chemical_list: D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D009944:Organoplatinum Compounds; D000077150:Oxaliplatin; D000068258:Bevacizumab; D000077146:Irinotecan; D002166:Camptothecin